Let Your Turfgrass Go Dormant
Many of today’s regionally adapted turfgrasses can handle a period of drought or heat. If you choose to let your turfgrass go dormant, follow these tips to help it thrive when better conditions prevail.
Turfgrass has the ability to go dormant during adverse conditions. Dormancy is simply a state of reduced water usage where the turfgrass plant focuses resources on the roots.
Summer dormancy is a normal response to the stress of heat and drought. Most turfgrass plants can stay in a dormant state for at least 3 to 4 weeks without the grass dying. The length of dormancy depends on the genetics of the species and the overall health of the plant.
Make sure the turfgrass is as healthy as possible before dormancy begins. Avoid stressing it once conditions become unfavorable. Dormant turfgrass will turn brown and is often considered unsightly, but it will recover when conditions improve.
Aid that recovery by following these tips.
If drought goes beyond the 4 weeks, apply enough water to re-hydrate the grass slightly and wet the soil down to a 5-inch (12.5 cm) depth. This will not green up the turfgrass in most cases, but will keep the plant alive.
Maintain the turfgrass at a slightly higher height of cut before and during a drought. To minimize stress, mow only as needed, early in the morning or late in the evening. Use a sharp blade and remove no more than one-third of the turfgrass leaf blade.
During dormancy caused by heat or drought, avoid excessive fertilization. The dormant turfgrass is not actively bringing in large quantities of nutrients. Excessive nitrogen applications before or during a drought can promote top growth at the expense of rooting activity and cause injury to the turfgrass plant.
Some weeds thrive during reduced water situations because of large tap roots that can hold water. A broadcast application of herbicide can further stress the dormant turfgrass. Instead, spot treat these weeds with an herbicide or remove the weeds by hand.
Because the turfgrass is dormant it is not able to readily repair itself so reduce traffic on the lawn as much as possible. Avoid any activity on the turfgrass during the heat of day. Foot traffic and even lawn mowers can injure the turfgrass plants and cause almost immediate dehydration.
When cooler, wetter weather returns, water deeply to restore soil moisture. This will wash dust off the leaves, rehydrate the dormant crowns and buds, and initiate root growth.